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11.
This study examined the effects of situational pressure and maternal characteristics (social contingent self-worth, controlling parenting attitudes) on mothers' autonomy support versus control in the social domain. Sixty 4th-grade children and their mothers worked on a laboratory task in preparation for meeting new children, with mothers in either an evaluation (mothers told their child would be evaluated by other children) or no-evaluation (no mention of evaluation) condition. Mothers in the evaluation condition spent more time giving answers to their children. Mothers with controlling parenting attitudes exhibited more controlling behavior. Further, mothers with high social contingent self-worth in the evaluation condition were most controlling. Results suggest the importance of interactions between situations and maternal characteristics in determining levels of mothers' autonomy support versus control and have implications for helping parents support children's autonomy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
12.
Well designed domain specific languages have three important benefits: (1) the easy expression of problems, (2) the application of domain specific optimizations (including parallelization), and (3) dramatic improvements in productivity for their users. In this paper we describe a compiler and parallel runtime system for modeling the complex kinetics of rubber vulcanization and olefin polymerization that achieves all of these goals. The compiler allows the development of a system of ordinary differential equations describing a complex vulcanization reaction or single-site olefin polymerization reaction—a task that used to require months—to be done in hours. A specialized common sub-expression elimination and other algebraic optimizations sufficiently simplify the complex machine generated code to allow it to be compiled—eliminating all but 8.0% of the operations in our largest program and enabling over 60 times faster execution on our largest benchmark codes. The parallel runtime and dynamic load balancing scheme enables fast simulations of the model.  相似文献   
13.
During self-motion, the world normally appears stationary. In part, this may be due to reductions in visual motion signals during self-motion. In 8 experiments, the authors used magnitude estimation to characterize changes in visual speed perception as a result of biomechanical self-motion alone (treadmill walking), physical translation alone (passive transport), and both biomechanical self-motion and physical translation together (walking). Their results show that each factor alone produces subtractive reductions in visual speed but that subtraction is greatest with both factors together, approximating the sum of the 2 separately. The similarity of results for biomechanical and passive self-motion support H. B. Barlow's (1990) inhibition theory of sensory correlation as a mechanism for implementing H. Wallach's (1987) compensation for self-motion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
14.
15.

Background

The cardiovascular effects of pulmonary exposure to engineered nanomaterials (ENM) are poorly understood, and the reproductive consequences are even less understood. Inflammation remains the most frequently explored mechanism of ENM toxicity. However, the key mediators and steps between lung exposure and uterine health remain to be fully defined. The purpose of this study was to determine the uterine inflammatory and vascular effects of pulmonary exposure to titanium dioxide nanoparticles (nano-TiO2). We hypothesized that pulmonary nano-TiO2 exposure initiates a Th2 inflammatory response mediated by Group II innate lymphoid cells (ILC2), which may be associated with an impairment in uterine microvascular reactivity.

Methods

Female, virgin, Sprague-Dawley rats (8–12 weeks) were exposed to 100 μg of nano-TiO2 via intratracheal instillation 24 h prior to microvascular assessments. Serial blood samples were obtained at 0, 1, 2 and 4 h post-exposure for multiplex cytokine analysis. ILC2 numbers in the lungs were determined. ILC2s were isolated and phosphorylated nuclear factor kappa-light-chain-enhancer of activated B cells (NF-?B) levels were measured. Pressure myography was used to assess vascular reactivity of isolated radial arterioles.

Results

Pulmonary nano-TiO2 exposure was associated with an increase in IL-1ß, 4, 5 and 13 and TNF- α 4 h post-exposure, indicative of an innate Th2 inflammatory response. ILC2 numbers were significantly increased in lungs from exposed animals (1.66?±?0.19%) compared to controls (0.19?±?0.22%). Phosphorylation of the transactivation domain (Ser-468) of NF-κB in isolated ILC2 and IL-33 in lung epithelial cells were significantly increased (126.8?±?4.3% and 137?±?11% of controls respectively) by nano-TiO2 exposure. Lastly, radial endothelium-dependent arteriolar reactivity was significantly impaired (27?±?12%), while endothelium-independent dilation (7?±?14%) and α-adrenergic sensitivity (8?±?2%) were not altered compared to control levels. Treatment with an anti- IL-33 antibody (1 mg/kg) 30 min prior to nano-TiO2 exposure resulted in a significant improvement in endothelium-dependent dilation and a decreased level of IL-33 in both plasma and bronchoalveolar lavage fluid.

Conclusions

These results provide evidence that the uterine microvascular dysfunction that follows pulmonary ENM exposure may be initiated via activation of lung-resident ILC2 and subsequent systemic Th2-dependent inflammation.
  相似文献   
16.
Among American children and adolescents aged 1 to 17 years, the 12- to 17-year-olds represent the largest users of outpatient mental health services. This study utilizes a nationally representative sample of this age group from the 2005 National Survey on Drug Use and Health to illuminate predictors of services use from three treatment settings: day treatment programs, mental health clinics/centers, and private/in-home settings. Univariate analyses were used to calculate the percentages of the study sample that used mental health services in these settings. In bivariate analyses, the authors estimated the strength of the associations between available predisposing, need, and enabling factors and the outcomes. Multiple logistic regressions estimated the independent effects of each covariate on the outcomes. Lifetime depression, lifetime general anxiety, delinquent behaviors, drug dependence, and Medicaid were consistent predictors of services use in the three treatment settings. Several other factors were associated with services use in bivariate analyses but lost most of their statistical significance when the authors adjusted for other confounders. Interpreted in light of its potential limitations, this study has important research and policy significance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
17.
(1) Background: Calcium-binding protein S100B is involved in neuroregeneration but has also been associated with neurodegeneration. These contrasting effects may result from concentration or duration of exposure. We investigated the effect of long-term increased S100B levels on amyloid-β processing in one-year-old transgenic (tg) mice with 12 copies of the murine S100B gene with specific consideration of sex and specific brain regions. (2) Methods: S100B and amyloid-β 42 (Aβ42) were quantified in serum, cerebrospinal fluid (CSF), adipose tissue, and different brain regions by ELISA in wild-type (wt) and S100Btg mice (each n = 7 per group). Thioflavin T (ThT) and Aβ immunostaining were performed for visualization of Aβ deposition. (3) Results: S100B in serum, CSF, and brain was significantly increased in S100Btg mice of both sexes. Aβ42 was significantly increased in the hippocampus of male S100Btg mice (p = 0.0075), and the frontal cortex of female S100Btg mice (p = 0.0262). ThT and Aβ immunostaining demonstrated Aβ deposition in different brain regions in S100Btg mice of both sexes and female wt. (4) Conclusion: Our data validate this experimental model for studying the role of S100B in neurodegeneration and indicate that Aβ processing is sex-dependent and brain region-specific, which deserves further investigation of signaling pathways and behavioral responses.  相似文献   
18.
[Correction Notice: An erratum for this article was reported in Vol 16(3) of Psychology of Addictive Behaviors (see record 2009-17717-001). On page 121, in the abstract, the penultimate sentence incorrectly reads, “As predicted, participants consumed more alcohol following the anxiety challenge than following the control task; however, the opposite pattern was evidenced for drinking following the 2 activities.” The sentence should read as follows: “As predicted, participants consumed more alcohol following the anxiety challenge than following the control task; however, the opposite pattern was evidenced for drinking preceding the 2 activities.”] K. Abrams, M. Kushner, K. Medina, and A. Voight (2001) showed that alcohol attenuates social anxiety symptoms in socially phobic individuals. This article examines whether social anxiety symptoms can lead to increased alcohol use in this same population. Forty-four individuals with social phobia attended 2 laboratory sessions, spaced 1 week apart, in groups of approximately 10. Participants underwent a social anxiety challenge during 1 session and a control task during the other. Half of the sample self-administered alcohol immediately before, and half immediately after, these 2 activities. As predicted, participants consumed more alcohol following the anxiety challenge than following the control task; however, the opposite pattern was evidenced for drinking following the 2 activities. These findings add to an understanding of why social phobia and alcohol problems tend to co-occur. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
19.

Background  

The study examined the effects of dietary fasting on physical balance among young healthy women.  相似文献   
20.
Much research has been dedicated to understanding the molecular basis of UV damage to biomolecules, yet many questions remain regarding the specific pathways involved. Here we describe a genome-mediated mechanism that causes site-specific virus protein cleavage upon UV irradiation. Bacteriophage MS2 was disinfected with 254 nm UV, and protein damage was characterized with ESI- and MALDI-based FT-ICR, Orbitrap, and TOF mass spectroscopy. Top-down mass spectrometry of the products identified the backbone cleavage site as Cys46-Ser47 in the virus capsid protein, a location of viral genome-protein interaction. The presence of viral RNA was essential to inducing backbone cleavage. The similar bacteriophage GA did not exhibit site-specific protein cleavage. Based on the major protein fragments identified by accurate mass analysis, a cleavage mechanism is proposed by radical formation. The mechanism involves initial oxidation of the Cys46 side chain followed by hydrogen atom abstraction from Ser47 C(α). Computational protein QM/MM studies confirmed the initial steps of the radical mechanism. Collectively, this study describes a rare incidence of genome-induced protein cleavage without the addition of sensitizers.  相似文献   
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